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Low salinity water flooding (LSWF) is a popular enhanced oil recovery technique. Among factors that affect the performance of LSWF, geochemical interaction at the oil-brine interface and the associated enterokinetic properties plays a prominent role. This work presents a triple-layer surface complexation model for predicting the zeta potential of the oil-brine interface. We improve upon previous modelling studies by incorporating the effects of (1) temperature variation, (2) basic (-NH) oil surface group interactions (3) adsorption of sodium ions on outer and inner Helmholtz planes and (4) the presence of sulphate ions in brine. Model validation against published experimental data shows model accuracy between 66% and 99%. The model displays higher accuracies at lower salinities (making it particularly suited for LSWF applications), intermediate pH and higher total acid number. In addition, a correlation between (-NH) site density and total acid/base numbers is proposed. A sensitivity study performed utilising the developed model showed that higher sulphate concentration in the brine and elevated temperature makes the zeta potential at the oil-brine interface more negative. In addition, the sensitivity study indicates that a higher concentration of basic polar oil compounds is less favourable as it may result in less water-wet conditions in the reservoir. [Display omitted] • Developed a triple-layer surface complexation model (TLM) to describe oil-brine interactions. • Addressed the limitations of the existing oil-brine triple-layer models. • Model Validation using data of 16 types of crude oil from 9 published experimental studies with accuracy between 66% and 99%. • A correlation between (-NH) site density and total acid/base numbers is proposed. • Results indicate that a higher concentration of basic polar oil compounds may result in less favourable wetting conditions. [ABSTRACT FROM AUTHOR]

Low salinity water flooding (LSWF) is a popular enhanced oil recovery technique. Among factors that affect the performance of LSWF, geochemical interaction at the oil-brine interface and the associated enterokinetic properties plays a prominent role. This work presents a triple-layer surface complexation model for predicting the zeta potential of the oil-brine interface. We improve upon previous modelling studies by incorporating the effects of (1) temperature variation, (2) basic (-NH) oil surface group interactions (3) adsorption of sodium ions on outer and inner Helmholtz planes and (4) the presence of sulphate ions in brine. Model validation against published experimental data shows model accuracy between 66% and 99%. The model displays higher accuracies at lower salinities (making it particularly suited for LSWF applications), intermediate pH and higher total acid number. In addition, a correlation between (-NH) site density and total acid/base numbers is proposed. A sensitivity study performed utilising the developed model showed that higher sulphate concentration in the brine and elevated temperature makes the zeta potential at the oil-brine interface more negative. In addition, the sensitivity study indicates that a higher concentration of basic polar oil compounds is less favourable as it may result in less water-wet conditions in the reservoir. [Display omitted] • Developed a triple-layer surface complexation model (TLM) to describe oil-brine interactions. • Addressed the limitations of the existing oil-brine triple-layer models. • Model Validation using data of 16 types of crude oil from 9 published experimental studies with accuracy between 66% and 99%. • A correlation between (-NH) site density and total acid/base numbers is proposed. • Results indicate that a higher concentration of basic polar oil compounds may result in less favourable wetting conditions. [ABSTRACT FROM AUTHOR]